This invention relates to peripheral toroidal blowers of the kind (hereinafter referred to as the kind specified) comprising a toroidal chamber which is divided along a plane at right angles to its axis into a part bounded by a stator housing having adjacent inlet and outlet ports with a stripper between them and a part bounded by a rotor housing containing a series of impeller blades. The impeller blades and the stripper are arranged in such a way that when the rotor housing is rotated a flow of air is induced into the chamber through the inlet port along a helical path, the axis of which extends around the toroidal chamber, and out of the chamber through the outlet port.